Piston ring arbor



May 2,'1933- T. E MCFALL Y 1,906,389

PISTON RING ARBOR Filed Feb. 26, 1930 y 3 Sheets-Sheet l {YR-orner@t Filed Feb 26 1930 3 Sheets-Sheet 2 7. Z. 5 Z 4% QW. Z a .//b a 3 T 5 4 Z 3.. 7 ou 9J o0 8 0 3 3/ ...wd w.. a. l. Z mm3 WN @NN mouaor Thur oLf. Fall Patented MayA 2, V1933 UNiTED STATESA PATENT oFfFicE .Application filed February 26, 1930. Serial No. 431,352.

This invention relates to a piston ring casting sawing machine and arbor for holding a plurality of the piston ringcastings in l position to be acted upon by a plurality of 5. saws, for the purpose of splitting the rings substantially midway between their opposite fiat sides and thereby making two narrower ring castings from each of the ring castings placed on the arbor. I have heretofore made 1 application in the UnitedStates Patent Oiice for a process of piston ring casting, said ap- Vplication having Sei'. No. 344,373 'filed March 5, 1929, ,which was allowed December" 20, 1929 and hasbecome Patent No. 1,749,147.

- The process of piston ring casting disclosed in said application contemplates using a pattern for ring castings of twice the width, plus allowances for shrinkage and machining of the piston rings which are to be manufactured, and after the ring castings have been produced from the pattern, splitting or dividing each casting substantially midway betweenpits opposite flat sides to thereby obtain from each of the original double width piston ring castings two ring castings of narrow Width, ofuniform character of metal throughout and with a complete elimination of hard spots of metal therein 'which are prevaient in individual ring castings for the 3 narrow width rings now almost universally used in internal combustion engines; and at the same time the two ring castings which are produced from each of the double width ring castings, after the process of splitting has been carrigd out, are produced at a cost but very little if any greater than one of the narrow width ring castings when the same are produced individually.

The present invention is directed to a very practical and eilicient mechanism including i a ring casting holding arbor whereby the ring castings of double width are readily split or cut substantially midway between 5 their flat sides, a plurality of the ring castings being operated upon simultaneously by a plurality of metal cutting saws thereby ef# fecting the ready division or splitting of the double ring castings each into two narrower width ring castings of the size desired for piston rings. The invention further con- \with antislip material, such as rubber,and

templates a novel construction of arbor for holding the double width ring castings in proper relation to each other and against movement on the arbor during the time that the sawing operation is .taking place. Many other obJects and purposes than those stated will be apparent upon understanding of the invention had fromv thefollowing descrip' tion,.taken in connection with the accompanying drawings, in which,

`Fig. 1 is a fragmentary front elevation, partly in section, illustrative of a machine for splitting a plurality of double ring castings each into two parts.

Fig. 2 is a fragmentary side elevation 65 thereof. l.

Fig. is an enlarged longitudinal vertical section through the expanding ring casting holding arbor of my invention, showing the arbor in collapsed condition.

Fig. 4 is a view similar to Fig. 3 showing the arbor expanded to engage and hold the ring castings. Y

Fig. 5 is an end elevation of theV arbor on a still'larger scale. 75

Fig. 6 is a fragmentaryelevation of one end .portion of the arbor.

Fig. 7 is an enlarged transverse vertical section through the arbor lshowing a ring casting around the saine before the arbor is expanded. Fig. 8 is a view similar to Fig. 7 illustrating the arbor expanded to hold the ring casting and the way in which a cutting saw bperates with respect thereto. 3

Fig. 9 is a fragmentary enlarged longitudina'l section through one of the members of the arbor, showing how the bottoms of the ring castings holding grooves may be lined Fig. 10 is a perspective view of a ring casting of the type which is to be split on'the inachine and of the kind shown, .described and claimed in another pending application for patent filed by me of even date herewith.

Like reference characters refer to like parts in the different figures ofthe drawings.

The machine for splitting the ring castings may comprise a vertical support 1 at the .100

. port 2 carrying a transverse guide member sel 3 with inclined side guides 4 at its opposed edges, upon which a horizontal table 5 is mounted for sliding movements, the table having cooperating downwardly extending guides 6 to engage with the guides 4, as

shown in Fig. 2, whereby the table may bev moved back and forth in a horizontal plane.

A heavy supporting arm 7, preferably of cylindrical form, is rigidly. secured at "one end to the upper` endv of the support 1 and extends horizontally therefrom .over the table 5. At its outer end it carries a downwardly extending arm 8 which in turn, near its lower end, is equipped with a suitable center 9 similar to a lathe tail stock center. A horizontal shaft 13 extends through the support 1 below the overhead support 7 and is journaled in the support 1 and its outwardly extending end is supported en the center 9. The shaft 13 is provided within the support 1 with a suitable driving pulley 11 around which a drive belt 12 passes by means of which the shaft 13 is rotated (see Fig. 1). This part of the structure is simllar to a conventional milling machinm'g construction.

In this machine the shaft 13 constitutes a saw arbor on which a plurality of circular metal cuttingsaws 15 are mounted, the vsaws l5 being held in spaced apart relation by spacing collars 16v interposed between them andthe saws and spacing collars are fixed to the arbor shaft 13 in a suitable conventional manner. The saws 15 and spacing collars 16 may be removed for sharpening or for replacement with others of different sizes by backing off the center 9 and swinging the lower end of thearm 8 to one side' clear of the forward end of the arbor shaft 13 from the forward end of which shaft the saws and spacing collars may be readily removed and replaced.

On the table 5 near each end thereof a head stock 17 is rigidly secured near the rear edge of the table while, similarly, near the front of the table and adjacent each end a tail stock 18 is rigidly secured. Each of the tail stocks is provided with the usual adjustable tail stock center 19. Ashaft 2O extends through and is rotatably mounted in each of the head stocks 17 and it is between the two head stocks and the two tail stocks that the ring holding arbors of my invention are to be mounted for sawing double thickness ring castings carried thereon.

In the construction of the ring holding arbors a circular plate 21, similar to a lathe face plate and through which a plurality of adjusting screws 22 pass, is pinned or otherwise secured on a central shaft 23 of the arbor which, at one end portion, or that end near which the plate 21 is secured, is flattened as indicated at 23a's'o that itgmay be detach- 25a. is assed over the shaft and may be seably connected with and driven from the head stock shaft 20, the opposite end of the shaft 23 being engaged by the pointed end of the tail stock center 19. The shaft 23 at a plurality of points between its ends, two being shown, is formed with integral conical enlargements 24. Near the end of the shaft 23 which engages with the tail stock center, a circular plate 25 having a central sleeve cured t ereon against rotating movement by a. keyscrew 26 threaded therethrough and at ts""nner end seating in a keyway slot in the shaft 23. The end portion -of the shaft 23 is threaded for a binding and adjusting 8 nut 27 which comes up against the outer face of the member 25. At the inner side or face of the member 25 a plurality of pins 28 project for engagement with the adjacent ends of the outwardlymovable parts or sections 29 of the expanding arbor, each of`said sections 29 at the end thereof adj acent the member 25 being slotted, as indicated at 28a, for the reception of the pins 28 (see Fig. 6).

A plurality of outwardly movable arbor members 29 are located around the shaft 23 and the conical enlargements thereon. In

.the construction shown four of these members 29 are used and are, at their outer surfaces, shaped substantially in the are lof a circle. Each at its inner side has a plurality of ribs 30 with conical inner surfaces to lit against and cooperate with the conical surfaces of the parts 24 on the shaft, whereby on relative longitudinal movement of the 1 shaft and member 29 with respect to each other in one direction said members 29 are forced outwardly. Each of the members 29 at each end thereof adjacent the plate 21 is somewhat enlarged and grooved, as indicated 1 at 31, so that when all four of the members are located around the shaft a continuous coiled spring tension band 32 may be seated in the groove, the tendency of which is to cause the arbor members to hug snugly 1 against the conical enlargements 24. The opposite end likewise has a grooved section 33 the exterior diameter of which is less than j the diameter of the grooved end section 31 and in which a second continuous coiled 1 spring bank 34 is seated.

The outer surface of each of the members 29 has a plurality of spaced apart transverse fianges 35 extending therefrom defining grooves each of which in the four arbor sec- 1 tions around the shaft 23 is adapted to receive a double width piston ring casting. The grooves at their lower middle portions are further provided with narrower grooves 36 the purpose of which will hereafter be de- 1 scribed.

At one radial side of one of the members 29 a flat plate 37 is attached, the outer edge of which extends a short distance outward beyond the bottoms of the grooves between l the flanges 35. It likewise, at spaced apart points, is formed with notches 36a in conjunction and alinement, with the narrower grooves 36 in the arbor sections 29, and the bottoms of the notches 36a reach to the bottoms of said narrower grooves 36.

Each of the double ring castings 38 at one point at its inner side is formed with a ltransverse notchor groove 39 (see Fig. 10). When the arbor is in collapsed condition, as in Fig. 3, a plurality of the ring castings 38 may be placed over the arbor and when so placed the plate 37 should be positioned vertically as shown in Fig. 7, while the notches or grooves 39 at the inner sides of the ring castings are to be located directly over the upper edge of the plate 37 so that as the ring castings drop by gravity between the flanges 35 the upper edge of the plate 37 enters the notches or grooves 39 therein. Then by screwing the nut 27 on the end of the arbor shaft 23 from the position shown in Fig. 3 to that shown in Fig. 4, the incline faced ribs` on said arbor sections 29 ride' upon the larger diameter portions of the conical sections 24 of the shaft 23, moving the arbor sections outward and stretching the springs 32 and 34.- `The outward movements of the arbor sections are guided through the pins 28 seating in the grooves 28a asshown in`Fig .,6.

The .extent to which the expanding arbor sections 29 may be moved outwardlyV is governed by the position of the screws 22 against which the ends of said sections 29 eventually come after which further outward movement I of said arbor sections isstopped. The screws over the smaller ends 33'of said parts 29.

22'by test, trial and experiment are properly set so that when the parts 29 abut there against the rings are seated in the ooves between the flanges 35 and the bottoms of the grooves bear tightly and firmly against the inner curved sides of the ringcastings. It will be noted that even when the arbor is in its collapsed condition, as shown in Fig. 3, the ring castings cannot'pass over the enlarged end parts 31 of the expanding arbor sections 29 but that the same may pass freely The flanges 35 serve to accurately space thev double width ring castings 38v so that the saws castings substantially midway between their opposite flatsides. The saws pass through to the inner sides of the ring castings and enter the grooves 36 and the notches 36a`in the plate 37 as shown in Fig. 8. The saw cut is indicated at 40, in dotted lines, in Fig. 10.

If for any reason itis desired that the rings the lining foi` each groove being in two partsone at each side ofl where the cutting saw 15 13. The rear end of each of the shafts 20y is provided with a sprocket 44 and a sprocket chain 43 passes around both of said sprockets 44 and also the sprocket 42 whereby the shafts 20 are rotated by and simultaneously with the arbor shaft 13. The proper direction of rotation of the shaft 20 with relation to the direction of rotation of theshaft 13 is obtained by the insertion of an idler gear in the train of gears 14 and the speed ratio of rotation between .the shafts 20 andthe arbor shaft 13 is properly governed by the ratios of the gears 14 and the' sprockets 42 and 44. It is conceived that clutches may be utilizedv to connect or disconnect the with double width ring castings 38 the table 5 may bemoved from the dotted line position shown in Fig. 1 to the full line position mov- .ing the ring castings underneath the saws 1 5 for splitting the ring castings-midway between their opposite flat sides. While such operation is taking place with respect to ring castings 0n the arbor brought l underneath the saws another arbor loaded line to the dotted line position shown in F ig.'1, sawing the ring castings on 'the last mentioned arbor while those which have been split will be removed and another arbor loaded with double width ring castings-put in place; andl it is during this operation .of inserting and taking laway the arbors from the machine that the clutch drive between the sprocket wheels 44 and the shafts 20 will be used.

The machine'itself of course may be equipped' with suitable driving mechanism for moving the table back and vforth and with reversing mechanism' for automatic reversal of movement of the table and the like, all of which are very old and well known, but so far as the present invention is concerned the table 5 maybe moved in-any manner,for instance, by hand..l The construction described is very practical for the purposes for which it has been designed and has so proved in pracwill pass through the double widtlrring cast-l tice. Large 'quantity production in the matbers around the shaft lengthwise thereof, in-l terengaging means between the shaft and the inner sides of said arbor members for moving said arbor members radially outward on longitudinal movement of said members in one direction along the shaft, a plurality of transverse flanges around the outer sides of said arbor members defining grooves between the flanges for the reception of the piston ring castings, each of said arbor members at the bottom of each groove therein between two adjacent flanges and midway between said flanges having a much narrower groove cut therein, and a fiat metal plate secured to a radial side of one of said arbor members having its outer edge extending a short distance beyond the bottoms of said first mentioned wider grooves and having notches therein in alinement and conjunction with the narrow grooves in said members at the bottoms of the wider grooves.

2. In a construction of the class described, an arbor shaft having a plurality of spaced conical enlargements thereon, a plate attached to the shaft toward one end thereof, adjusting screws threaded through the plate, a plurality of inwardly and outwardly movable arbor members around the shaft each having a plurality of ribs at its inner side whereby circumferential and axial movement may be had therebetween, means on said members defining grooves wherein ring castings may be located and means for moving the shaft'aud said members longitudinally with inclined sides to cooperate with and engage against the surfaces of the conical enlargements on the shaft, means on said arbor. members in which ring castings may be l0- cated, a second plate slidably vmounted on the opposite end portion of the shaft, a nut threaded on said opposite end portion against said plate for moving said arbor members toward the adjusting screws carried by the first plate and bring their ends against the ends of said adjusting screws and thereby move the arbor members outwardly against ring castings located around it and stop said movement at a predetermined point, said arbor members having slots therein, and pins rigid with said second plate extending into said slots for the purpose described.

3. A construction of the class described comprising, a shaft having a plurality of spaced apart enlargements thereon of conical form, a plurality of arbor members located around the shaft in spaced relation and having at their inner sides cooperating inclined sides of circular conical form to engage against said conical enlargements on the shaft with respect to each other to force said grooved members outwardly and thereby seat the ring castings in the grooves of said mem- -bers and hold said castings against movement with respect thereto. In testimony whereof I aix my signature.

` THURLOW E. MGFALL. 

